Inshot burner

ABSTRACT

An inshot burner is provided including a burner body and a nozzle assembly provided in an outlet opening of the burner body. The nozzle assembly includes a disc-like member having a central hole therein and a plurality of radially spaced holes spaced around a perimeter of the central hole. A tube member is disposed in the central hole of the disc-like member.

FIELD OF THE INVENTION

The present invention relates to inshot burners and more particularly aninshot burner with an improved construction.

BACKGROUND AND SUMMARY OF THE INVENTION

Inshot burners are used to blend a mixture of air and a gaseous fuel topresent a combustible product for ignition and flow through a heatexchanger employed in a furnace for heating air. The inshot burnerutilizes a mixing tube arranged in conjunction with a nozzle forsupplying a gaseous fuel so that the energy in the gaseous fuel is usedto induce a flow of air from the ambient into the tube in proportionsdesigned to provide a desired mixture of fuel and air.

Inshot gas burners, such as used in furnaces, typically include aventuri tube which diverges from its input end to an enlarged outputend. In some constructions, a burner head insert made of sintered orpowered metal having outlet openings is mounted in the outlet end of thetube. In operation, gas is injected into the inlet end of the burnerentraining air into the burner with it. This primary air/gas mixtureflows through the tube to the burner head or flame retention insert. Theprimary air/gas mixture passes through the insert and burns as it exitsthe insert forming a cone of flame projecting from the outer face.

Some of the problems associated with conventional inshot burner designsare flame stability and noise. The velocity of the primary air/gas flowfrom the insert is often greater than the flame speed. Under thiscondition, the flame lifts off from the burner insert; i.e., the flamebegins to burn in mid-air at a location spaced from the outer face ofthe flame retention insert. Flame lift-off is a major cause of noiseassociated with the operation of inshot burners. If the velocity of theair/gas mixture is too slow when compared to the flame speed, flashbackcan occur. Flashback is the burning of the gas within the burner nozzleitself. This condition can cause overheating and deterioration of thenozzle. Another key aspect of burner design is burning efficiency or theability to achieve more complete combustion of the gas/air mixture. Anincreased performance of more complete combustion also leads toreduction in emissions of CO and NOx.

Accordingly, the present invention provides an improved inshot gasburner which is designed to increase the efficiency of combustion and tooperate quieter than conventional inshot burners. In addition, theimproved design reduces overall manufacturing costs while allowing amore ordered flame pattern that serves to control secondary airentrainment and to allow for more complete combustion of the gas/airmixture.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating the preferred embodiment of the invention, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a side view of the inshot burner according to the principlesof the present invention;

FIG. 2 is a top view of the burner body utilized in the inshot burneraccording to the principles of the present invention;

FIG. 3 is a side view of the burner body shown in FIG. 2;

FIG. 4 is an end view of a disc-like nozzle insert which forms part ofthe nozzle assembly according to the principles of the presentinvention;

FIG. 5 is a side view of the disc-like nozzle member of FIG. 4;

FIG. 6 is a side view of a nozzle tube which forms part of the nozzleassembly of the present invention;

FIG. 7 is an end view of the nozzle tube shown in FIG. 6;

FIG. 8 is a side view of the mounting bracket assembly according to theprinciples of the present invention;

FIG. 9 is a top view of a bottom bracket of the mounting bracketassembly;

FIG. 10 is a front view of the bottom bracket shown in FIG. 9;

FIG. 11 is a side view of the bottom bracket shown in FIG. 9;

FIG. 12 is a top view of the top bracket of the mounting bracketassembly shown in FIG. 8;

FIG. 13 is a side view of the top bracket shown in FIG. 12; and

FIG. 14 is a front view of the top bracket shown in FIG. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the preferred embodiment(s) is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

With reference to FIG. 1, an inshot burner 10, according to theprinciples of the present invention, is shown. The burner 10 has fivecomponent parts that make up the complete assembly. A burner body 12, asbest illustrated in FIGS. 2 and 3 is fabricated from a one inchilluminized tube having a 0.065 inch thickness wall. An inch and a halffrom the back of the tube 12, a reduced diameter portion 14 is providedto create a special shape for the air intake 16. A bead 18 is formed onopposite sides of the burner body in the area of a reduced diameterportion 20. The beads 18 are used to locate the burner body 12, as willbe described in greater detail herein. The back of the tube 14 is formedto locate the back of the burner 10 over an orifice that feeds gas tothe burner and also forms a window for the primary air intake.

The outlet opening 22 at the second end of the burner body is expandedoutward to approximately 1.25 inch in diameter and is provided with adepth of approximately 0.2 inch to make a seat portion 24 for holdingthe burner nozzle assembly 26. Two port holes 28 are locatedapproximately 0.325 inches from the front of the burner on each side tosupply the gas for cross-lighting between the burners.

The burner nozzle assembly 26 includes a disc-like member 30, best shownin FIGS. 4 and 5 and a nozzle tube 32, best shown in FIGS. 6 and 7. Thedisc-like plate 30 is received in the seat portion 24 in the opening endof the burner body 12. The disc-like member 30 is preferably made frompowdered metal and is approximately 0.25 inch thick having a 1.25 inchdiameter. The center of the nozzle has a 0.63 inch diameter hole 34 forreceiving the nozzle tube 32 therein. There are 12 0.156 inch diameterholes 36 spaced around the perimeter of the center hole 34.

The nozzle tube 32 has an upstream end portion 32A provided with alarger diameter than a downstream end portion 32B. The nozzle tube 32 isshaped in position in such a manner that when assembled to the nozzleplate 30, the nozzle allows the burner to be specifically tuned fordifferent applications to reduce NOx generation. The increased diameterportion at the upstream end 32A and reduced diameter portion 32B at thedownstream end of the nozzle tube 32 lowers the velocity of gas and airmixture going to the outer ports 36. The design makes the burneroperation quieter and stops lift-off and lowers emissions from theburner.

A pair of mounting brackets 40, 42 are formed to fit the contour of theburner body 12. As best shown in FIGS. 9-11, the bottom bracket 40 haslocating slots 44 provided in the radially extending flange portion 46to locate the burner 10 to a burner box (not shown). The bottom bracket40 has a lip 48 defined by a turned up flange in front of the bracket 40which extends over to the nozzle tube 32 and helps the burner to operatequieter and eliminates lift-off. The flange portion 46 creates a pocket50 between the top and bottom bracket 42, 40 that directs the gas fromthe side ports 28 of the burner body 12 to create chain lighting. Thetop bracket 42 has a pair of radially extending flange portions 52 eachprovided with a raised portion 54 which, along with the flange portions46 of the bottom bracket 40 define the pockets 50.

During assembly, the nozzle tube 32 is inserted in the opening 34 of thedisc-plate member 30. Depending upon the specific intended applicationof the burner 10, the nozzle tube 32 is specifically located within theopening 34. In particular, it has been found that for differentapplications, the location of the nozzle tube 32 can be specificallytuned to increase the burner efficiency and reduce emissions.Accordingly, the axial position of the nozzle tube 32 relative to thenozzle plate 30 can be specifically determined for optimum efficiencyand reduced emissions for different applications. Nozzle assembly 26 isthen assembled in the outlet opening 24 of the burner body 12, and thebrackets 40, 42 are assembled to the burner body 12 and projected weldedin place. The lips 48 of the bottom bracket 40 extend radially inwardand engage the nozzle tube 32.

The description of the invention is merely exemplary in nature and,thus, variations that do not depart from the gist of the invention areintended to be within the scope of the invention. Such variations arenot to be regarded as a departure from the spirit and scope of theinvention.

1. A burner, comprising: a burner body including an inlet opening at oneend thereof and an outlet opening at a second end thereof; a nozzleassembly disposed in said outlet opening of said burner body, saidnozzle assembly including a disc-like member having a central holetherein and a plurality of radially spaced holes spaced around aperimeter of said central hole, and a tube member disposed in saidcentral hole and extending axially beyond said outlet opening of saidburner body.
 2. The burner according to claim 1, wherein said tubemember includes a first end and a second end wherein said first end hasa larger diameter than said second end.
 3. The burner according to claim1, further comprising a bracket mounted to said burner body andincluding a pair of radially inwardly extending lips that extend infront of said nozzle assembly.
 4. The burner according to claim 1,further comprising a bracket assembly mounted to said burner body anddefining a pair of pockets extending radially from said burner body andcommunicating with openings disposed in said burner body.
 5. The burneraccording to claim 4, wherein said bracket assembly includes a pair ofradially inwardly extending lips that extend in front of said nozzleassembly.
 6. The burner according to claim 4, wherein said bracketassembly includes a bottom bracket and a top bracket that are connectedto one another and encircle said burner body.
 7. The burner according toclaim 4, wherein said bracket assembly includes a bottom bracket and atop bracket that are welded together.
 8. The burner according to claim1, further comprising a bracket assembly mounted to said burner body,said bracket assembly including a pair of radially extending flangeswith locating slots disposed in an edge thereof for locating the burnerin a burner box.
 9. A nozzle for a burner, comprising: a disc-likemember having a central hole therein and a plurality of radially spacedholes spaced around a perimeter of said central hole; and a tube memberdisposed in said central hole and including a first end and a second endwherein said first end has a larger diameter than said second end. 10.The nozzle according to claim 9, wherein said tube member is welded tosaid disc-like member.
 11. The nozzle according to claim 9, wherein saidcenter hole in said disc-like member has a diameter that is greater thanhalf of a diameter of said disc-like member.
 12. A burner, comprising: aburner body including an inlet opening at one end thereof and an outletopening at a second end thereof; a nozzle assembly disposed in saidoutlet opening of said burner body, said nozzle assembly including adisc-like member having a central hole therein and a plurality ofradially spaced holes spaced around a perimeter of said central hole,and a tube member disposed in said central hole, said tube memberincluding an upstream end and a downstream end wherein said upstream endhas a larger diameter than said downstream end.
 13. The burner accordingto claim 12, further comprising a bracket mounted to said burner bodyand including a pair of radially inwardly extending lips that extend infront of said nozzle assembly.
 14. The burner according to claim 12,further comprising a bracket assembly mounted to said burner body anddefining a pair of pockets extending radially from said burner body andcommunicating with openings disposed in said burner body.
 15. The burneraccording to claim 14, wherein said bracket assembly includes a pair ofradially inwardly extending lips that extend in front of said nozzleassembly.
 16. The burner according to claim 14, wherein said bracketassembly includes a bottom bracket and a top bracket that are connectedto one another and encircle said burner body.
 17. The burner accordingto claim 14, wherein said bracket assembly includes a bottom bracket anda top bracket that are welded together.
 18. The burner according toclaim 12, further comprising a bracket assembly mounted to said burnerbody, said bracket assembly including a pair of radially extendingflanges with locating slots disposed in an edge thereof for locating theburner in a burner box.
 19. A burner, comprising: a burner bodyincluding an inlet opening at one end thereof and an outlet opening at asecond end thereof; a nozzle assembly disposed in said outlet opening ofsaid burner body, said nozzle assembly including a disc-like memberhaving a central hole therein and a plurality of radially spaced holesspaced around a perimeter of said central hole, and a tube memberdisposed in said central hole; and a mounting bracket assembly mountedto said burner body and defining a pair of pockets extending radiallyfrom said burner body and communicating with openings disposed in saidburner body, said mounting bracket assembly including an top bracket anda bottom bracket that encircle said burner body.
 20. A method of tuninga burner for use in different applications, comprising the steps of:providing an elongated burner body having an inlet opening and an outletopening; mounting a nozzle assembly in said outlet opening of saidelongated burner body, said nozzle assembly including a disc-like memberhaving a central hole therein and a plurality of radially spaced holesspaced around a perimeter of said central hole, and a tube memberdisposed in said central hole, said tube member being positioned toextend axially from a front and rear surface of said disc-like membersuch that an axial position thereof is predetermined based upon theburner application.
 21. The method of claim 20, further comprising thesteps of mounting a top and a bottom bracket to said burner body. 22.The method of claim 21, wherein said top and bottom brackets define apair of pockets therebetween extending radially from said burner bodyand communicating with side openings in said burner body.